This invention in general relates to a re-usable liner that can be used for making textures into concrete, as well as a form liner for securing and sealing objects in a form so that when a wall is poured the objects remain fixed to the surface by being partially embedded when the form and the liner are withdrawn.
The construction industry in the last several decades has taken advantage of the cost and structural benefits of simulated brick or simulated stone walls over traditional masonry, and decorative designs. The method typically uses a form liner to create shapes and textures to create a decorative poured wall that can later be stained to look like traditional masonry and designs. A liner has also been used to place real brick, pavers or stones within the liner itself. The liner typically consists of a number of recessed areas separated by joints. The recessed areas are where the pavers, brick or stone are placed and the joints between the recessed areas holds the brick, pavers or stones from moving out of place. Typically a concrete slurry is then poured into the form and allowed to cure. The joints form a “grout line” around the pavers bricks or stones when concrete is poured into the form. Once the concrete is cured and the form and the liner is removed, a simulated wall is revealed with the stone, brick or pavers exposed on the surface and concrete exposed between the brick, stones or pavers which is the grout line. The goal is to make the poured wall look like real masonry. Architects criticize that using a liner to create textures and then stain makes the wall look fake, that embedding bricks or pavers creates a wall that does not look like natural masonry because the grout joints are all the same width, that bricks are too uniform in size and, in some applications, that the created joints are flat rather than semicircular as the joints of hand laid brick.
Over the years there have been a number of different types of form liners have been used, each with various drawbacks. All of these liners added to cost and labor, especially when forming inlayed brick into poured walls.
Solid urethane liners have been used for a number of years, but not for embedding objects in a poured wall when there is a full tooled joint. A full tooled joint is a joint that has a semicircular top and the sides of the joint and extends down to touch the bottom part of the brick that fits into the cavity. The full “tooled joint” or a semicircular joint, is the preferred architectural design because it is the standard masonry joint between the brick. The joint used with urethane liners is a flat joint, also called raked joint urethane liners. Such liners are expensive, labor intensive and the result is typically an unnatural looking wall. They are not used in the precast industry when used to embed objects into the surface of a wall with a natural full tooled joint; not only because of the expensive price per square foot but it is difficult to get urethanes soft enough to seal bricks and allow for variable brick sizes to fit into the cavity between the joints.
U.S. Pat. No. 5,900,180 is an attempt for an inexpensive way of producing flat joint or raked joint liners using foam. It is manufactured by die cutting or routing a foam sheet into a grid pattern with square grout joints and gluing it to a paper backing. The areas that are die cut, specifically each vertical edge of every grout joint is a problem because the concrete sticks to the exposed cells of the foam. When the form is removed, the liner breaks apart and the foam joints are stuck in the concrete panel between the brick pavers, resulting in costly cleaning due to manually scraping out the foam pieces from the grout lines of the simulated brick wall. The design disclosed in U.S. Pat. No. 5,900,180 does not allow for variable sized brick because it was designed so that the foam grid is glued to a flat backing that is not flexible, causing the foam grid to be fixed where the foam meets the backing. The recessed area where brick pavers seat require very tight tolerances in the brick pavers. If the bricks are too large, the foam material does not have give and pushes the brick upward out of the recessed area resulting in a misalignment. The expensive cost of grinding the brick, waxing the brick and manually scraping the foam out of the finished wall has made this liner an undesirable product to use. Furthermore, this reference with its flat and uniform grout joints segregates this liner to another type of architectural look, a liner that makes the wall look fabricated and not like real masonry.
Prior plastic liners such as the VersaLiner™ panel manufactured by Innovative Brick Systems, Inc. of Bloomfield, Colo. have been able to achieve a tooled joint but in doing so they have encountered many problems due to the rigid nature of the panel material and particularly the rigid nature of the semicircular joints between the recessed brick-receiving regions. These hard plastic joints define uniform brick-receiving regions in the liner panel which, in turn, require the use of brick pavers that are cut to very precise tolerances to fit close to the grout joint. The problem is that the cementous material seeps around the joint and to the brick face because there is no seal by the hard plastic against the brick edge. Further, the grout lines of plastic liners are not malleable and the grout joint cannot adjust to oversized brick pavers (i.e. 1/16 inch or more out of specification in either the length or the height dimension) will not be seated correctly in the liner, partially seated on top of the grout joint and not able to seat in the cavity between the grout joints causing unacceptable visual defects in the finished wall. In order to ensure that the finished brick wall may be cleaned of any concrete material on the front face of the bricks, it is typically necessary to use specialized brick pavers that have had their faces coated with wax. Upon completion of the formed wall and the removal of the plastic liner panels, a hot water (high pressure) spray is applied to the face of the brick wall to remove the wax coating and any accumulated concrete material. This process is very labor intensive and costly to the contractor. It is worthy to note that the prewaxed brick pavers are expensive and even more expensive when the brick edges must be ground to fit the exact dimensions of the hard plastic liner, nearly doubling the cost of a standard brick paver. The plastic liners are not thermally stable, rising temperatures can cause the liner to expand and create even larger gaps between the brick pavers and the joints. Lower temperatures can cause the bricks to pop out of the brick cavity and seat on top of the grout joint. With all of the precision needed in the rigid plastic liner and the brick to make a brick faced wall, the result is a prefabricated wall that does not look hand laid. This liner is typically used one time and then discarded because it becomes destroyed when the concrete wall panel is removed from the form.
U.S. Publication 2006/0180731 A1 is another attempt to produce a tooled joint liner but has its own problems. U.S. Publication 2006/0180731 A1 is a laborious production method in which polystyrene extruded foam head joints are formed and cut separately from the polystyrene extruded foam bed joints. The individual joints are individually positioned in grooves on a conveyor belt track and the backing sheet is run simultaneously with the backing sheet under a heat roller which attaches the individual foam joints to the backing sheet. The recessed areas where the brick pavers are laid is sugar coated to act as a retarding agent for leaking concrete because the device does not completely seal the brick. The strips are glued directly to the backing and the recessed area has no flexibility because the bottom is glued to the paper. The reference states that when a brick is oversized, the contractor can detach the individual head joint and move it over and reattach the joint so that the brick will fit in. This creates a problem for the adjacent brick because the recessed cavity will be too short. The contractor must try to find a very small brick, cut the brick down or move the next joint over which continues to compound the problem. At some point in the row, brick pavers must be cut or ground which is very expensive and labor intensive. The reference tries to address the problem if a brick is too long by detaching the grout joint, but the reference liner fails to address the problem of a brick being too wide. This results in the probability that the contractor would purchase expensive precut brick and prewaxed brick to be safe from onsite grinding and extensive cleaning. Due to its material makeup, the reference liner can only be used once, the contractor must layout new liner for each pour which adds even more to the labor cost. Furthermore the grouts are made all with the exact same shape and the end results in prefabricated looking brick wall.
There remains a need for a form liner capable of being used with bricks and/or other inserts of various sizes without modification, capable of forming joints having the visual characteristics of a tooled mortar joint, capable of creating a wall section with realistic imperfections, and capable of being used multiple times.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.